Local Pages

Saturday, September 12, 2009

A new Marker Oscillator

This is my first completed HB DipTrace Designed PCB using Toner Transfer Method. The board is 1.25 x .75 inches with 16mil signal traces. Time to build this project, from Pressing "Print", to "Turn on" was about 1 hour.

This project is a 30m Marker Oscillator with Key Switch.

The oscillator uses all SMD parts, except; the Voltage Regulator (LM7805), Switch, Crystal, Trim Cap, and the Antenna (the Cap with a lead sticking straight up) which are full size components.

It worked the first time and was on frequency with just a twist of the Trim Cap, it seems to be very temperature stable and hand capacitance does not seem to effect frequency. I am very pleased!

Solder Paste applied and Ready for SMD Parts

SMD Parts on, Ready for Oven or Soldering Iron, In my case I used a small tip soldering iron. That is the 2N3904 SMD oscillator in the centre. The thing that looks like a TO-92 transistor (see below) is the LM7805M voltage regulator.

Completed and Aligned to Frequency on 30m at 10.140100mHz,
at top of QRSS Segment and bottom of WSPR Segment.